1. Field of the Invention
The present invention relates to a storage type air conditioning system including a plurality of air conditioners each having a storage battery which can store external power, and an operation method and a control program for the storage type air conditioning system.
2. Description of the Related Art
Reduction of emission of carbon dioxide (CO2) as one greenhouse gas has been recently required to prevent global warming. In order to reduce the emission of CO2, it is important to make power supply more efficient on the basis of equalization of power demand. Power demand for air conditioning is known as one of factors inducing disparity in power demand of a day, and it is estimated that the factor of pushing up the peak value of the power demand resides in that air conditioners are actuated all together in the daytime during the summer season or the like. In order to solve such a problem, a storage type air conditioner has been hitherto known (for example, see JP-A-2002-309927).
Generally, a storage type air conditioner has a storage battery, and it charges the storage battery in the nighttime in which power demand is little and discharges the storage battery in the daytime to execute air conditioning operation by using stored power. If such a storage type air conditioner is utilized, it contributes to equalization of power demand and thus reduces the power generation amount of an electric power company, whereby the emission of CO2 can be reduced.
However, when the conventional storage type air conditioner has stored power more than the power amount (electric energy) required for its own air conditioning operation, it has been impossible to effectively use this extra stored power and thus further equalize the power demand.